Added Level Sets Don't Add

Whenever I try to add a newly converted .slc file to Sokoban program, after I add it to the directory and refresh the file list, nothing happens. The new level set does not show up and sometimes, it causes the entire program to freeze up.

You can not add newly converted .slc files to the program. The current new program will only accept, what has been added to the site, due to the special new slc header, which handles the upload and download of scores. You can not make such a .slc yourself, since the colletion needs to be "registered". The only way to do that is by submitting to the site. Without this you could upload fake or invalid scores of the collection, which is not in the database.

I've been able to add collections in the past...? Maybe these collections were collections that were already on the site. I know that was the case with the Hyper Rectangular and Infinity sets, but SBMendonca, Sokobig 70, Sokobig 80, and a few other level sets were able to be added without the need for them to be on the site...